de (Greek #1161)
but, and, etc.
KJV usage: also, and, but, moreover, now (often unexpressed in English).
Pronounce: deh
Origin: a primary particle (adversative or continuative)
dei (Greek #1163)
also δέον (deh-on'); neuter active participle of the same; both used impersonally; it is (was, etc.) necessary (as binding)
KJV usage: behoved, be meet, must (needs), (be) need(-ful), ought, should.
Pronounce: die
Origin: 3d person singular active present of 1210